Visual Sheep Scores
About this guide
Visually assessed traits are included in the breeding objective of all
stud and commercial sheep breeders, regardless of their target market
or environment.
Following extensive industry consultation, Australian Wool Innovation
Limited (AWI) and Meat and Livestock Australia (MLA) has developed
this first-of-its-kind guide to:
• Provide the Australian sheep industry with a standardised set
of visual assessment scores for the consistent description of
important phenotypic traits of all breeds of sheep;
• Develop a quick and simple scoring system to help sheep classers
and breeders select sheep on visually-assessed traits to accelerate
genetic gain;
• Enable sheep breeders and classers to record and submit visual
score data and genetic information to Sheep Genetics to progress
development of across-flock Australian Sheep Breeding Values*
(ASBVs) for visually-assessed traits; and,
• Enable researchers to validate the heritability of visually-assessed
sheep traits, and to measure their relationships, if any, on important
production traits such as fleece weight, fibre diameter, growth rate
and body weight.
In addition, the visual standards and scoring system contained in
this guide are endorsed by the Australian Merino Sire Evaluation
Association (AMSEA), and include all compulsory traits visually
assessed at Central Test Sire Evaluation sites across Australia.
* Developed by Sheep Genetics, a joint initiative of AWI and MLA,
ASBVs enable ram breeders and commercial sheep producers to
compare the genetic potential of rams and ewes for a range of
production traits, independent of the environment and location.
Using Visual Sheep Scores
1. Wool Quality traits
This guide provides the Australian sheep industry with a common
language for the visual description, recording and classing of all
breeds of sheep according to important visual traits.
2. Conformation traits
Visual Sheep Scores are designed for ram and sheep breeders that
choose to class and select animals on one or any number of visuallyassessed traits as part of their overall breeding objective.
Visual scores gathered on individual animals may be submitted to
Sheep Genetics with other pedigree and performance information to
assist the sheep industry with the development of across-flock ASBVs
for visually-assessed traits.
Designed for use on both male and female sheep equally, the 19 sets
of Visual Sheep Scores provided in this guide have been divided into
three sections:
3. Breech traits*
A set of illustrative standards and simple instructions on ‘how’ and
‘when’ to visually score animals are provided for each trait, however,
unless otherwise stated:
• A single score of 1, 2, 3, 4 or 5 is recorded for each trait.
(This includes ‘combined’ traits, where the highest score of the
multiple sites is recorded); and,
• Score 1 depicts LEAST expression of the trait and Score 5 depicts
MOST expression (i.e. rule of thumb is Score 1 is LESS and Score
5 is MORE of each trait).
* Please note: the visual breech traits contained in this guide
replace the visual standards and scoring scale contained in the
AWI Visual Breech Scores guide published in May 2006.
Using Wool Quality Scores
Visual Wool Quality Scores provide visual standards for the description
of physical fleece and fibre traits that contribute to the economic value
of wool.
These scores are designed for ram breeders and commercial
woolgrowers who choose to class and select animals on one or
more of these visual traits as part of their overall breeding objective.
This guide contains a set of Wool Quality Scores for 10 traits.
Visual scores of 1 to 5 are provided for eight traits, and scores of
1 and 5 only for the two binary traits (recessive black lamb and
random spot).
With the exception of wool character, Score 1 depicts LEAST
expression of the trait and Score 5 depicts MOST expression
(i.e. rule of thumb is Score 1 is LESS and Score 5 is MORE of
each trait).
In all cases, a single score is recorded for each trait. This includes the
two ‘combined’ traits (fibre pigmentation and non-fibre pigmentation),
where the highest score of the multiple sites is recorded.
In addition, it is essential that the two pigmentation traits random spot
(Australian piebald) and recessive black lamb (Agouti gene) are scored
and recorded separately from fibre pigmentation.
Data gathered on individual animals may also be submitted to Sheep
Genetics with other pedigree and performance information to assist
the sheep industry with the development of across-flock ASBVs for
various wool quality traits.
Visual Wool Quality Scores can be taken on both male and female
sheep at various ages. It is essential to record the age of the animal
when scores are taken, with the optimal age recommended in the
table below.
Wool Trait
Age
When
Fleece rot
•
Over 9 months
•
Classing or shearing, provided a minimum of 6 months (or 40 millimetres) of wool growth
Wool colour
•
Over 9 months
•
Classing or shearing, provided a minimum of 6 months (or 40 millimetres) of wool growth
Wool character
•
Over 9 months
•
Classing or shearing, provided a minimum of 6 months (or 40 millimetres) of wool growth
Dust penetration
•
Over 9 months
•
Classing or shearing, provided a minimum of 6 months (or 40 millimetres) of wool growth
Staple weathering
•
Over 9 months
•
Classing or shearing, provided a minimum of 6 months (or 40 millimetres) of wool growth
Staple structure
•
Over 9 months
•
Classing or shearing, provided a minimum of 6 months (or 40 millimetres) of wool growth
Fibre pigmentation
•
6 to 10 weeks
•
Lamb marking*
Non-fibre pigmentation
•
6 to 10 weeks
•
Lamb marking
Recessive black
•
6 to 10 weeks
•
Lamb marking
Random spot
•
6 to 10 weeks
•
Lamb marking*
* Score data can be submitted to Sheep Genetics if pigmentation is identified after lamb marking such as classing or shearing
For further information about the development or use of these Visual Wool Quality Scores contact:
Sheep Genetics
Australian Merino Sire Evaluation Association
Tel: +61 2 6773 2948 Email: [email protected]
Tel: +61 2 6743 2306 Email: [email protected]
Web: www.sheepgenetics.org.au
Web: mss.csiro.au
Note: fleece rot should not be confused with Dermatitis (or ‘lumpy
wool’), which tends to form columns of hard lumps along the staple.
Fleece rot
Age: Over 9 months.
When: Classing or shearing, provided a minimum of 6 months
(or 40 millimetres) of wool growth.
How to score: Open the fleece at a minimum of three sites along
the backline and look for evidence of staining and bands of crusting.
The highest score across the sites is recorded.
Caused by moisture and bacterial growth at skin level, fleece rot refers
to the degree of wool discolouration and/or crusted banding across
wool fibres and parallel to the skin. Discoloured bands can be yellow,
green, red-orange, pink-violet, blue, brown or grey in colour.
Rule of thumb: An animal with Score 1 has no bacterial colour
or staining. An animal with Score 5 has bands of ‘crusting’ greater
than 5 millimetres wide, with or without bacterial staining.
Score 1:
Score 2:
Score 3:
Score 4:
Score 5:
No bacterial colouring or
staining.
Band of bacterial staining
<10mm wide with no
crusting.
Band of bacterial staining
>10mm wide with no
crusting.
Band of crusting <5mm
wide, with or without
bacterial staining.
Band of crusting >5mm
wide, with or without
bacterial staining.
Fleece rot
Score 1
Score 2
Score 3
Score 4
Score 5
Wool colour
Age: Over 9 months.
When: Classing or shearing, provided a minimum of 6 months
(or 40 millimetres) of wool growth.
Wool colour describes the degree of whiteness of greasy wool.
How to score: Open the fleece at a minimum of three sites –
side of shoulder, mid-side and hip. The highest score across the
sites is recorded.
Rule of thumb: An animal with Score 1 has the ‘brightest’ white
wool, whereas a Score 5 animal has yellow wool.
Wool colour
Score 1
Score 2
Score 3
Score 4
Score 5
How to score: Open the fleece at a minimum of three sites –
side of shoulder, mid-side and hip. The highest score across the
sites is recorded.
Wool character
Age: Over 9 months.
When: Classing or shearing, provided a minimum of 6 months
(or 40 millimetres) of wool growth.
Wool character describes both the definition of crimp and variation
of crimp frequency between fibres and along the staple.
Rule of thumb: An animal with Score 1 has well-defined crimp along
the entire length of the staple. A Score 5 animal has large areas of
‘flat’ wool due to a large variation in crimp frequency and/or definition
of fibres along the staple.
Score 1:
Score 2:
Score 3:
Score 4:
Score 5:
No variation; consistent,
well-defined crimp and
regular crimp frequency
along the entire length of
the staple.
Staple still shows welldefined crimp, but not
totally consistent crimp
frequency and/or crimp
definition along the
entire staple.
Some staple crimp
still visible, but crimp
frequency and/or crimp
definition of fibres
becoming inconsistent.
Areas of staple with
no visible crimp due to
large variation in crimp
frequency and/or crimp
definition of fibres along
the staple.
Total variation; large areas
of staple with no visible
crimp due to inconsistent
crimp frequency and/or
crimp definition of fibres
along the staple.
Wool character
Score 1
Score 2
Score 3
Score 4
Score 5
How to score: Open the fleece at a minimum of three sites along
the backline. The highest score across the sites is recorded.
Dust penetration
Age: Over 9 months.
When: Classing or shearing, provided a minimum of 6 months
(or 40 millimetres) of wool growth.
Dust penetration is the degree of deterioration of the staple due to the
penetration of dust. Note: research has shown that penetration of dust
down the staple is not closely related to dust content in Merino wool
and, therefore, is a poor indicator of fleece yield.
Rule of thumb: An animal with Score 1 has no weathering or
dust penetration and is equivalent to a coated fleece in a shed
environment. A Score 5 animal has extensive weathering and dust
penetration almost the entire length of the staple.
Score 1:
Score 2:
Score 3:
Score 4:
Score 5:
Staple is free of dust
penetration with only the
tip of wool affected by
dust i.e. <5% of staple.
Staple has some dust
penetration beyond the tip
i.e. 5-10% of staple.
Penetration of dust well
beyond the tip of the
staple i.e. 10-30% of
staple.
Dust penetration
significantly into the fleece
i.e. 30-70% of staple.
Dust penetration can be
seen down to the skin,
particularly along the
backline i.e. 80-100%
of staple.
Dust penetration
Score 1
Score 2
Score 3
Score 4
Score 5
How to score: Open the fleece at a minimum of three sites along
the backline. The highest score across the sites is recorded.
Staple weathering
Age: Over 9 months.
When: Classing or shearing, provided a minimum of 6 months
(or 40 millimetres) of wool growth.
Staple weathering is the degree of deterioration of the staple due to
penetration of light and water.
Rule of thumb: An animal with Score 1 has no visual weathering
and is equivalent to a coated fleece in a shed environment. A Score
5 animal has extensive weathering and deterioration of fibre structure
along the majority of the length of the staple.
Score 1:
Score 2:
Score 3:
Score 4:
Score 5:
Staple has no visible
weathering or
deterioration of fibre
structure; tip comprises
<5% of staple.
No visible weathering of
tip but some deterioration
of fibre structure i.e.
<10% of staple ‘swollen’.
Some weathering of tip
i.e. 5–10% of staple;
moderate deterioration
of fibre structure i.e. 1020% of staple ‘swollen’.
Moderate weathering of
tip i.e. 10–20% of staple;
significant deterioration of
fibre structure i.e 20-30%
of staple ‘swollen’.
Extensive weathering
and deterioration of fibre
structure i.e. ‘paint brush’
tip comprises >20% of
staple, with 30-50%
‘swollen’.
Staple weathering
Score 1
Score 2
Score 3
Score 4
Score 5
How to score: Open the fleece at a minimum of three sites – side
of shoulder, mid-side and hip. The highest score across the sites
is recorded.
Staple structure
Age: Over 9 months.
When: Classing or shearing, provided a minimum of 6 months
(or 40 millimetres) of wool growth.
Staple structure describes the cluster arrangement of the fibre
bundles comprising each staple, in particular the size and diameter
of each staple.
Rule of thumb: An animal with Score 1 has extremely fine fibre
bundles, whereas a Score 5 animal has extremely large bundles of
fibres which make the staple ‘blocky’ in appearance.
Score 1:
Score 2:
Score 3:
Score 4:
Score 5:
Staple comprises very
fine bundles i.e. staple
width of less than 5mm
in diameter.
Staple comprises fine
bundles i.e. staple width
of 5-10mm in diameter.
Staple comprises medium
bundles i.e. staple width
of 10-20mm in diameter.
Staple comprises large
bundles i.e. staple width
of 20-30mm in diameter.
‘Blocky’ staple comprising
extremely large bundles
i.e. staple width of 3050mm in diameter.
Staple structure
< 5mm
5 – 10mm
10 – 20mm
20 – 30mm
30 – 50mm
Score 2
Score 3
Score 4
Score 5
fibre bundle
Score 1
How to score: A single score of 1, 2, 3, 4 or 5. The highest score
(i.e. percentage of fibres) of a particular site – body, ears, legs,
eyelashes and back of neck (birthcoat halo-hair) – is recorded.
Fibre pigmentation
Age: 6 to 10 weeks
When: Lamb marking*.
Fibre pigmentation is a combined trait. It refers to the percentage
of dark fibres on any part of the animal, particularly the body, ears,
legs, eyelashes and back of neck (birthcoat halo-hair). Pigmented
fibres are normally black, grey or red-tan in colour. Importantly,
fibre pigmentation is scored separately from random spot
(Australian piebald) and recessive black lamb (Agouti gene).
Rule of thumb: If the body, ears, legs and eyelashes have no
pigmentation (Score 1), but if 51-75% of the fibres on the back of
neck are birthcoat halo-hairs (Score 4), then Score 4 is the overall
score recorded for the trait.
* Score data can be submitted to Sheep Genetics if pigmentation is
identified after lamb marking such as classing or shearing.
Score 1:
Score 2:
Score 3:
Score 4:
Score 5:
No pigmentation
i.e. 0% pigmented
fibres at any site.
1-25% pigmented fibres
at one or more sites.
26-50% pigmented fibres
at one or more sites.
51-75% pigmented fibres
at at one or more sites.
76-100% pigmented
fibres at one or more
sites.
Fibre pigmentation
Score 1
Score 2
Score 3
Score 4
Score 5
How to score: A single score of 1, 2, 3, 4 or 5. The highest score
of the various sites is recorded.
Non-fibre pigmentation
Age: 6 to 10 weeks.
When: Lamb marking.
Non-fibre pigmentation (skin/hoof) is a combined trait. It refers to the
percentage of pigmentation on the areas of the sheep that are not shorn,
in particular the bare skin of the nose, lips, eyelids and hooves.
Pigmented skin and hooves are normally brown-tan or black-grey
in colour.
Rule of thumb: A Score 1 animal has no skin or hoof pigmentation
at all. If an animal has no pigmentation (Score 1) on the nose, lips
or eyelids, but 51-75% of the total hoof area is pigmented (Score 4),
then Score 4 is the overall score recorded for the trait.
Score 1:
Score 2:
Score 3:
Score 4:
Score 5:
No pigmented area i.e.
0% of all bare skin sites
and all four hooves.
1–25% pigmented area
of one or more bare skin
sites and/or 1-25% of
the total hoof area.
26–50% pigmented area
of one or more bare skin
sites and/or 26-50% of
the total hoof area.
51–75% pigmented area
of one or more bare skin
sites and/or 51-75% of
the total hoof area.
76–100% pigmented area
of one or more bare skin
sites and/or 76-100% of
the total hoof area.
Non-fibre pigmentation
Score 1
Score 2
Score 3
Score 4
Score 5
Recessive black
How to score: A single score of 1 or 5.
Age: 6 to 10 weeks.
Rule of thumb: If an animal has relatively symmetrical markings on
both sides of the face then it is going to be one of the recessive black
patterns (Score 5) of ‘spotted self-colour’, ‘badgerface’ or ‘reverse
badgerface’. Note: If the face is completely white or has a random
pattern on one side of the face (i.e. non-symmetrical), the animal
should be scored as random spot.
When: Lamb marking.
Caused by the ‘symmetrical’ Agouti gene, recessive black refers to
the presence of pigmented wool or hair fibres anywhere on the face
or body. Pigmented fibres can be black, dark and light grey, brown or
tan in colour. Importantly, recessive black is scored separately from
random spot and fibre pigmentation.
Recessive black
badgerface
Score 1
reversed badgerface
Score 5
spotted self-colour
Random spot
How to score: A single score of 1 or 5.
Age: 6 to 10 weeks.
Rule of thumb: A random pattern is characterised as a rounded,
pigmented wool or hair spot; usually only one or, if more than one,
not symmetrically positioned (i.e. distributed unevenly to one side of
the face or body). Note: If both sides of the face or body are spotted
(i.e. symmetrical), the animal should be scored as recessive black.
When: Lamb marking*.
Random spot (Australian piebald) refers to the presence of a distinct
patch of pigmented fibres anywhere on the face or body, ranging from
small to large in size. Pigmented fibres are normally black-grey in
colour. Importantly, random spot is scored separately from recessive
black and fibre pigmentation.
* Score data can be submitted to Sheep Genetics if pigmentation is
identified after lamb marking such as classing or shearing.
Random spot
Score 1
Score 5
Using Conformation Scores
Visual Conformation Scores provide visual standards for the
description of physical body and structural traits that influence the
soundness and productivity of sheep and wool flocks.
These scores are designed for ram breeders and commercial
producers who choose to class and select animals on one or more of
these visual traits as part of their overall breeding objective.
This guide contains a set of Visual Conformation Scores of 1 to 5 for
five traits. Importantly, the ‘Score 1 is LEAST‘ and ‘Score 5 is MOST’
scoring scale does not apply to three conformation traits – jaw, feet/
legs and shoulder/back.
In these cases, Score 1 depicts VERY GOOD expression, Score
3 depicts AVERAGE expression and Score 5 depicts VERY BAD
expression of the trait.
A single score is recorded for all conformation traits. This includes
‘combined’ traits (feet/legs and shoulder/back), where the highest
score of the multiple sites is recorded.
Data gathered on individual animals may also be submitted to Sheep
Genetics with other pedigree and performance information to assist
the sheep industry with the development of across-flock ASBVs for
various conformation traits.
Visual Conformation Scores can be taken on both male and female
sheep at various ages. It is essential to record the age of the animal
when scores are taken, with the optimal age recommended in the
table below.
Conformation Trait
Age
When
Jaw
•
Over 4 months
•
Anytime after weaning, ideally at classing
Legs/Feet
•
Over 4 months
•
Anytime after weaning, ideally at classing
Shoulder/Back
•
Over 4 months
•
Anytime after weaning, post-shearing recommended
Face cover
•
Over 4 months
•
Minimum 4 months wool
Body wrinkle
•
Over 4 months
•
Anytime after weaning, post-shearing recommended
For further information about the development or use of these Visual Conformation Scores contact:
Sheep Genetics
Australian Merino Sire Evaluation Association
Tel: +61 2 6743 2306 Email: [email protected]
Tel: +61 2 6773 2948 Email: [email protected]
Web: www.sheepgenetics.org.au
Web: mss.csiro.au
Rule of thumb: The upper and lower jaws of a Score 1 animal line up
squarely at the teeth i.e. teeth rest ‘on the pad’, whereas a Score 5
animal has either a heavily ‘undershot’ or heavily ‘overshot’ jaw.
Jaw
Age: Over 4 months.
When: Anytime, ideally at classing.
Jaw refers to the soundness of jaw structure, in particular the
alignment of the lower jaw (and teeth) relative to the top jaw.
How to score: A single score of 1, 2, 3, 4 or 5.
Score 1:
Score 3:
Score 5:
Very Good: upper and
lower jaws line up
squarely at the teeth i.e.
teeth rest ‘on the pad’.
Average: jaw is marginally
‘undershot’ or ‘overshot’;
lower jaw is slightly
shorter or longer than the
upper jaw.
Very Poor: heavily
‘undershot’
or ‘overshot’ jaw; lower jaw
is significantly shorter or
longer than the upper jaw.
Jaw
Score 1
Score 3
Score 5
How to score: A single score of 1, 2, 3, 4 or 5. The highest score
across the leg and feet components of all four legs is recorded.
Legs/Feet
Age: Over 4 months.
When: Anytime, ideally at classing.
Legs/Feet is a combined trait. It refers to the overall soundness of the
front and back leg and feet structure, in particular the orientation of the
legs/feet and angulation of the hocks and pasterns in relation to the feet.
Rule of thumb: If the stance, hocks and pasterns of the back legs and
feet are ‘very good’ (Score 1), but the pasterns of the front legs are
‘very poor’ (Score 5), then Score 5 is the overall score recorded for
the trait.
Score 1:
Score 2:
Score 3:
Score 4:
Score 5:
Very Good: good width of
stance; straight legs that
stand squarely over the
feet; moderate hock and
pastern angulation.
Good.
Average: significant hock
angulation, and/or legs
and feet orientating slightly
inwards or outwards, and/
or slightly ‘weak’ pasterns.
Poor.
Very Poor: extreme
angulation of hocks,
and/or legs orientating
inwards with hocks
touching or ‘bowed’
outwards, and/or very
‘weak’ pasterns.
Legs/Feet
Score 1
Score 3
Score 5
Shoulder/Back
How to score: A single score of 1, 2, 3, 4 or 5.
Age: Over 4 months.
Rule of thumb: An animal with Score 1 has angular shoulders
and a perfectly straight back between the top of the shoulder blades
and hips. A Score 5 animal has shoulder blades that sit well above
(or well below) the spine to create an extremely ‘dipped’ backline.
When: Anytime after weaning, post-shearing recommended.
A combined trait, shoulder/back refers to the soundness of the
shoulder blades and their positioning in relation to the neck and spine.
Score 1:
Score 2:
Score 3:
Score 4:
Score 5:
Very Good: shoulder
blades sit squarely
either side of the spine
i.e. no trough or ridge
between the shoulders;
back straight between
shoulders and hips.
Good.
Average: shoulders
positioned below the
spine to create a ‘ridge’
or above the spine to
create a ‘trough’ between
the shoulder blades;
back dips slightly behind
the shoulders.
Poor.
Very Poor: extremely high and
wide shoulder blades that
create a deep ‘trough’ above
the spine or extremely low
and narrow shoulder blades
that create a sharp ‘ridge’
above the spine; back dips
severely behind the shoulders.
Shoulder/Back
Score 1
Score 3
Score 5
Rule of thumb: An animal with Score 1 has an open face with no
wool on the jowls or top of the head. A Score 5 animal has wool
covering its entire face, commonly referred to as ‘wool blind’.
Face cover
Age: Over 4 months.
When: Minimum of 4 months wool.
Face cover refers to the degree of wool cover on the face, including
the top of head and jowl.
How to score: A single score of 1, 2, 3, 4 or 5.
Score 1:
Score 2:
Score 3:
Score 4:
Score 5:
Open face with no wool
in front of the ears and
topknot, or on the jowls.
Wool cover over the top
of head; some on the side
of muzzle, but not joined
between the ears and
eyes.
Wool cover over the top
of head and on the side
of muzzle; wool joined
between the ears and
eyes.
Wool cover from the top
of the head down the
muzzle; clear channel
remains between the eye
and the mouth.
Heavy wool growth over
the entire face; wool from
the top and side of the
muzzle joining.
Face cover
Score 1
Score 2
Score 3
Score 4
Score 5
Rule of thumb: An animal with Score 1 has a plain body with no
wrinkles. A Score 5 animal has extensive wrinkles and heavy folds of
skin over its entire body.
Body wrinkle
Age: Over 4 months.
When: Anytime after weaning, post-shearing recommended.
Body wrinkle refers to the degree and quantity of wrinkle on the body.
Neck wrinkle is highly related to body wrinkle, hence a single score for
body wrinkle will provide a reliable visual description for both traits.
How to score: A single score of 1, 2, 3, 4 or 5.
Score 1:
Score 2:
Score 3:
Score 4:
Score 5:
Plain-bodied animal with
no body wrinkle.
Plain body type with a few
small wrinkles over the
shoulders and hip region.
Slight wrinkling over the
length of the body.
Heavy wrinkling over the
entire body.
Extensive wrinkling and
heavy folds of skin over
entire body.
Body wrinkle
Score 1
Score 2
Score 3
Score 4
Score 5
About Visual Breech Scores
The recording of Visual Breech Scores and selection for these traits has
the potential to reduce the susceptibility of sheep to breech flystrike.
Following extensive industry consultation, Australian Wool Innovation
Limited (AWI) and Meat and Livestock Australia (MLA) has developed
this breech scoring system to:
• Provide a quick and simple breech scoring system to help ram
breeders and commercial producers select sheep for desirable
breech characteristics that are less susceptible to flystrike; and
• Estimate the heritability of these Visual Breech Scores (traits) and
measure their impact, if any, on important production traits such
as fleece weight, fibre diameter and body weight.
These Visual Breech Scores have also been developed with the aim
of generating sufficient data (on unmulesed animals only) to assist
Sheep Genetics with the development of Australian Sheep Breeding
Values (ASBVs) for each of these traits.
Sheep Genetics, a joint initiative of AWI and MLA, is designed to
enable ram breeders and commercial producers to compare animals
from different flocks on genetic merit (by ASBVs) using measured and
visually scored data.
Desirable breech traits
1. Breech Wrinkle
Breech flystrike of sheep is a consequence of wrinkle and wool in the
breech area that allows wet dags (urine and/or faeces) to create an
environment conducive to the laying and hatching of blowfly larvae.
2. Breech Cover
Research has already shown that each of the following are valuable
tools to reducing susceptibility to breech flystrike but, individually, are
not enough to significantly reduce breech flystrike:
• selection for plain (no wrinkle) breech;
• selection for reduced wool cover on the breech; and,
• selection against the tendency to scour, and form dags.
It is believed that genetic improvement of breech flystrike resistance
of sheep can be achieved through the complementary selection of
animals for the following four ‘indicator’ traits:
3. Crutch Cover
4. Dag Score
Consequently, this set of Visual Breech Scores has been developed for
each trait and various age groups. AWI-funded research is underway
to investigate the effects of breeding and the selection of Merino
sheep using this breech scoring system over a range of environments.
The effectiveness and commercial impact of breeding for these
‘indicator’ traits, however, will remain unknown until this research
is completed.
Using Visual Breech Scores
Visual Breech Scores provide standard scores for physical breech
traits that are thought to reduce the susceptibility of Merino sheep
flocks to breech flystrike.
This guide contains a set of Visual Breech Scores of 1 to 5 for four
traits – Breech Wrinkle, Breech Cover, Crutch Cover and Dag.
In each case, Score 1 depicts LEAST expression of the trait and Score
5 depicts MOST expression (i.e. rule of thumb is Score 1 is LESS and
Score 5 is MORE of each trait).
These scores are available for use by ram breeders and commercial
woolgrowers who choose to score animals and select on these traits
for breech flystrike resistance. If doing so, it should be remembered
that mulesing can affect the physical expression (and breech score)
of each trait.
Data gathered on individual animals (unmulesed only) may be
submitted to Sheep Genetics with other pedigree and performance
information to assist with the development of across-flock ASBVs
for traits for breech flystrike resistance.
Visual Breech Scores can be taken on both male and female sheep
at various ages. It is essential to record the age of the animal when
scores are taken, recommended in the table below.
Remember, profitable selection is based on identifying traits that have
significant commercial value. When selecting traits for your breeding
objective, ensure the selection balance is maintained. Be mindful
of all traits that determine the commercial profitability and quality
of your flock.
Please note: the visual breech traits and contained in this guide
replace the visual standards and scoring scale contained in the
AWI Visual Breech Scores guide published in May 2006.
Trait
Age
When
Breech Cover
6 to 10 weeks
Over 4 months
Lamb marking, preferably in the cradle
Anytime, ideally at weaning or classing
Crutch Cover
Over 4 months
Anytime, ideally at crutching or shearing
Breech Wrinkle
6 to 10 weeks
Over 4 months
Lamb marking
Crutching or post-shearing
Dag
Over 4 months
Prior to crutching
For further information about the development or use of these Visual Breech Scores contact:
AWI Helpline 1800 070 099 or visit www.wool.com.au
Breech Cover – Lambs
How to score: A single score of 1, 2, 3, 4 or 5.
Age: 6 to 10 weeks.
Rule of thumb: A Score 1 animal has natural bare area that extends
outwards around the anus and vulva, and right down to the bottom of
the breech area (the channel). An animal with Score 5 has complete
(most) wool cover i.e. no natural bare area at all.
When: Lamb marking, preferably in the cradle.
Breech Cover score refers to the amount of natural bare skin around
the perineum and breech area, in particular, the depth and width of
bare skin below and surrounding the vulva or anus.
Note: only visual scores on unmulesed animals (or lambs prior to
mulesing) can be submitted to Sheep Genetics.
Breech Cover – Lambs
Score 1
Score 2
Score 3
Score 4
Score 5
Breech Cover
How to score: A single score of 1, 2, 3, 4 or 5.
Age: Over 4 months.
Rule of thumb: A Score 1 animal has natural bare area that extends
outwards around the anus and vulva, and right down to the bottom of
the breech area (the channel). An animal with Score 5 has complete
(most) wool cover i.e. no natural bare area at all.
When: Anytime, ideally at weaning or classing.
Breech Cover score refers to the amount of natural bare skin around the
perineum and breech area, in particular, the depth and width of bare
skin below and surrounding the vulva or anus.
Note: only visual scores on unmulesed animals (or lambs prior to
mulesing) can be submitted to Sheep Genetics.
Breech Cover
Score 1
Score 2
Score 3
Score 4
Score 5
Crutch Cover
How to score: A single score of 1, 2, 3, 4 or 5.
Age: Over 4 months.
Rule of thumb: A Score 1 animal has natural bare area that extends
completely throughout the pubic and groin region, and extends through
to the animal’s breech, as well as right down the inside back legs beyond
the hocks. An animal with Score 5 has complete (most) wool cover i.e.
no bare area at all.
When: Anytime, ideally at crutching or shearing.
Crutch Cover score refers to the amount of natural bare skin from which
wool would normally be removed by the first blow during crutching, in
particular, the pubic area, groin and inside back legs.
Note: visual scores on unmulesed animals only (or lambs prior to
mulesing) can be submitted to Sheep Genetics.
Crutch Cover
Score 1
Score 2
Score 3
Score 4
Score 5
Breech Wrinkle – Lambs
Age: 6 to 10 weeks.
When: Lamb marking.
Breech Wrinkle refers to the degree of wrinkle at the tail set and down
the hind legs.
Note: visual scores on unmulesed animals only (or lambs prior to
mulesing) can be submitted to Sheep Genetics.
How to score: A single score of 1, 2, 3, 4 or 5. The highest score of
either the tail set or leg zone is recorded.
Rule of thumb: An animal with Score 1 has no wrinkle. A Score 5
animal has extensive wrinkle at the tail set and extending down the hind
legs to the hocks.
Breech Wrinkle – Lambs
Score 1
Score 2
Score 3
Score 4
Score 5
Breech Wrinkle
Age: Over 4 months.
When: Crutching or post-shearing.
Breech Wrinkle refers to the degree of wrinkle at the tail set and down
the hind legs.
Note: visual scores on unmulesed animals only (or lambs prior to
mulesing) can be submitted to Sheep Genetics.
How to score: A single score of 1, 2, 3, 4 or 5. The highest score of
either the tail set or leg zone is recorded.
Rule of thumb: An animal with Score 1 has no wrinkle. A Score 5
animal has extensive wrinkle at the tail set and extending down the hind
legs to the hocks.
Breech Wrinkle
Score 1
Score 2
Score 3
Score 4
Score 5
Dag
How to score: A single score of 1, 2, 3, 4 or 5.
Age: Over 4 months.
Rule of thumb: An animal with Score 1 has no dags. A Score 5 animal
has extensive dags not only remaining in the breech area, but extending
right down the hind legs to the pasterns.
When: Prior to crutching; 60 days following ‘the break’ to the dominant
rainfall season or when 30 to 40 per cent of flock is scouring.
Dag formation is caused by the adhesion of faecal material to the breech
area. Dag scores refer to the quantity of faecal material adhering to the
wool surrounding the breech and extending down the hind legs.
Note: visual scores on unmulesed animals only (or lambs prior to
mulesing) can be submitted to Sheep Genetics.
Dag
Score 1
Score 2
Score 3
Score 4
Score 5
Acknowledgements
AWI sincerely acknowledges the time and commitment provided by all
sheep breeders, classers and researchers involved in the development
of this guide, in particular members of the Executive Committee of the
Australian Merino Sire Evaluation Association.
Disclaimer
In compiling the information contained in these Visual Sheep Scores, Australian Wool Innovation Limited and Meat and Livestock Australia Limited has used its best endeavours to ensure that the information is correct and
current at the time of publication but takes no responsibility for any error, omission or defect therein.
These Visual Sheep Scores cover the information required to score sheep for use as an additional tool in selection and breeding decisions. Selection of traits to include in breeding objectives involves identifying profitability of all
aspects of sheep and wool production. Use of these scores for selection and breeding should be carried out with appropriate guidance.
To the extent permitted by law, Australian Wool Innovation Limited and Meat and Livestock Australia Limited, and its employees, agents and consultants exclude all liability for any loss or damage (including indirect, special or
consequential loss or damage) arising from the use of, or reliance on, these Visual Sheep Scores whether or not caused by any negligent act or omission.
Australian Wool
Innovation Limited
Meat & Livestock
Australia Limited
Sheep Genetics
Australian Merino Sire
Evaluation Association
GPO Box 4177,
Sydney NSW 2001
Tel: +61 2 9299 5155
Fax: +61 2 9299 9880
Locked Bag 991
North Sydney NSW 2059
Tel: +61 2 9463 9333
Fax: +61 2 9463 9393
PO Box U254, University of New England
Armidale, NSW 2351
Tel +61 2 6773 2948
Fax +61 2 6773 2707
“Gartmore”
Gunnedah NSW 2380
Tel: +61 2 6743 2306
Fax: +61 2 6743 2307
www.wool.com.au
www.mla.com.au
www.sheepgenetics.org.au
mss.csiro.au
September 2007
ISBN 1 92090 871 4